public class foundnine {
    public static void main(String[] args) {
        System.out.println("1-100中9出现的次数：");
        int num = 0;
        for (int i = 1; i <= 100; i++) {
            if(i%10==9||i/10==9){
                num++;
            }
        }
        System.out.println(num);
    }
}
